[FEATURE] Enable Setters for lazy getters

[GregDThomas]

Describe the feature
Currently, a @Getter(lazy = true) requires the annotated field to be marked final.

It would be great if this requirement was lifted, and a generated setter for that field was something like (extending the sample for the docs) ...

With lombok:

@Getter(lazy=true) @Setter private double[] cached = expensive();

Without lombok:

public double[] getCached()  {
   ... unchanged from current behaviour ...
}

public void setCached(double[] actualValue) {
    this.cached.set(actualValue == null ? this.cached : actualValue);
}

Describe the target audience
This would be useful anywhere the "expensive" value is not immutable.